Any benefit to adding thin insulation under wood paneling on uninsulated ceiling?
We recently purchased a mid-century home that had been painted white from top-to-bottom. We’re going to take some time and restore it to more original finishes but one of our plans is to put up wood (something like nickel-gap cherry) in between the beams in the room pictured here.
As far as we can tell, the roof is completely uninsulated which is a definite issue in the upper Midwest. We do plan on taking the whole roof off, adding 6″ or so of rigid foam, and then replacing the EPDM or adding a standing-seam metal roof, but that project is likely ~3-5 years off.
So with that backstory, we had the thought that it might be useful to put a layer of 1″ or 1.5″ insulation in between the beams, underneath the 3/4″ cherry we’re planning on using. We’ll caulk the exterior edges where there are obvious gaps currently but would it be worth the time and energy to add the foam? It’d likely “only” be R-9 if we do go with the 1.5″ thick polyiso, which of course wouldn’t be continuous and would only add R-value in between the beams. However, some coverage at R-9 is surely better than the whole thing being uninsulated..
Just trying to think through plusses and minuses.. should we be worried about trapping moisture? Anything else?
Replies
https://en.wikipedia.org/wiki/R-value_(insulation) has some interesting discussion.
Of course, R-9 is better than nothing, and will continue to save energy and money after the rest of the insulation is upgraded.
https://www.ecohome.net/guides/2254/polyisocyanurate-foam-is-a-hot-new-building-product-learn-where-and-where-not-to-use-it/
Has some discussion on various insulation board materials. Includes some info on thermal performance at reduced temperatures (when you want it to resist loosing your expensive heat to the great outdoors)
You might want to consider using Rock wool for the spaces between those beams.
You certainly want to consider how the interim and long term improvements will handle moisture, considering your location and habits inside the house.